Indicating apparatus



Sept. 9, i941. R. H, wlLMETH INDIGATING APPARATUS Filed July 6, 1959 3 Sheets-Sheet l Sept. 9, 1941. R. H. wlLMETH INDICATING APPARATUS Filed July 6, 1939 5 Sheets-Sheet 2 www buuf Sept- 9, l941. RH. WILMETH 2-255,372

INDICATING APPARATUS Filed July 6, 1959 `3 Sheets-Sheet I5 Patented Sept. 9, 1941 ICE.

IN DICATING APPARATUS Roscoe H. Wilmeth, Springfield, Ill., assignor to Sangamo Electric Company, Springiield, Ill., a corporation of Illinois appiication July 6, 1939, Serial No. 283,127

(Cl. YY1- 34) 17 Claims.

My invention relates, generally, to integrating apparatus and it has particular relation to apparatus for integrating maximum demands ofa varying quantity.

O-nev well known mechanism for integrating a varying quantity isa watthour meter. Itis provided., with electromagnets that are energized in accordance with the voltage across and the current flowingin an electrical circuit. The electromagnets are arranged to rotate a disc, the number orrevolutions of which corresponds'to the quantity of electrical energy that has been used.

The-number of revolutions of the disc iscounted by suitably intergeared pointers operating over scales which are calibrated in suitable-units. For measuring; electricalenergy, the scales are calibrated in units of watthours or kilowatt hours. If the pointers are rotated in accordance with any other varying quantity then, ofcourse, the calibration would be in different units. For purposes of illustration, it will be understood that a Watthour mechanism is employed as showing one application for the present invention. However, other applications will be apparent to those skilled in the art.

An integrating meter, such asY a watthour meter, measures the total energy thathas been used-during a period, suchY as a month; However, it gives-"0 indication of how much energy was being used at any one time or within whatis known as a demand interval, which usually is relatively short, such as fifteen or thirty minutes. It is-necessary for the power company to provide suflicient generating apparatus and a distribution system `having sulicient capacity to take care of the maximum demand for energy, even though this amount of energy. is requiredV relatively infrequently, for example, only once or twice during a demand period, suchVA asa month'. Therefore, it isdesirable to provide some means for indicating ther maximum demand oi a customer during a demand period in order to obtain a proper basis for charging him for the amountr of service that he has required.

In the past, an indication of the maximum demand of a customer has beenprovided by adding to the usual watthour meter and register a miximum demand pointer and a scale relative to which it can move. A pusher arm that is periodically reset, for example, every fteen or thirty minutes, constituting a demandv interval, is arranged to move the maximum demand pointer along the scale. The pointer is of the friction type andtends to. remain in the posiiton to which it is operated by the pusher arm. The position rCn of the maximum demand pointer relative to the scale indicates the maximum demand that has been applied to the system by a particular customer during` a demand period, such as a month.

t the end of the demand period, a meter reader notes the position of the maximum demand pointe-r relative to the scale and then resets it to its initial or zero position for the next demand period.

In many instances the penalty for exceeding a certain maximum demand during the demand period is quite severe. Therefore, it is necessary to insure that the maximum demand has been properlyl noted by the meter reader.

It will be apparent that, once the maximum demand pointer has been reset, it is impossible to subsequently check the accuracy of the record made by the meter reader in the event that a dispute arises between the customer and the power company. Itis highly desirable that some means be provided for preserving the maximum demand indication for some time after the meter is read, for example, during the next demand period, so thatv thereading can be checked if it becomes necessary to do so. It is to the provision of a mechanism for preserving this reading that the present invention is particularly addressed.

Therefore, it is an object of my invention, generally stated, to provide an improved form of cumulative maximum demand register.

An object of my invention is to add to the total of the previous maximum demands the maximum demand that has occurred during a succeeding demand period, the addition being effected independently of the resetting of the demand member that is advanced during the demandV period.

Another object of my invention is to advance one or more staiis during a demand period to positions corresponding to the maximum demand during a demand interval in the period and then, at the end of the demand period, to advance one or more pointers along scales to positions corresponding to the positions to which the staff or staffs have been advanced.

Still another object of my invention is to block movement of the staiis while the pointers are being advanced.

A further object of my invention is to prevent a subsequent advance of the pointers until a predetermined interval has elapsed after the preceding advance thereof.

A still further object of the invention is to compensate for. back lash in the gear train between the demand member and the staffs, in order to insure accuracy of integration.

Other objects of my invention will, in part, be obvious and, in part, appear hereinafter.

My invention, accordingly, is disclosed in the embodiment thereof shown in the accompanying drawings, and it comprises the features of construction, combination of elements and arrangement of parts which will be exemplied in the construction hereinafter set forth, and the scope of the application of which will be indicated in the appended claims.

For a more complete understanding of th nature and scope of my invention, reference may be had to the following detailed description, taken in connection with the accompanying drawings, in which- Figure 1 is a view, in front elevation, of the face of a cumulative maximum demand register constructed in accordance with the present invention;

Figures 2A and 2B, taken together, are isometric views of the parts making up the cumulative demand register, the relationship of the parts being somewhat diagrammatic and the scale for Figure 2A being slightly larger than the scale for Figure 2B in order to show the relationship of the parts as clearly as possible;

Figure 3 is a detail view, showing the demand wheel in elevation and the arrangement of the associated parts for compensating for .back lash; and

Figure 4 is a detail View, showing the blocking lever in elevation, illustrating the relation between the interval cam shaft and the blocking lever whereby a subsequent advancement of the cumulative pointers is prevented until a predetermined interval has elapsed after they have once been advanced.

Referring now particularly to Figure 1 of the drawings, it will be observed that the reference character I designates, generally, a cumulative maximum demand register that is arranged to be substituted for the usual integrating register of a meter, such as a Watthour meter, that is employed for measuring a varying quantity. The register I0 is provided with pointers II, I2, I3 and I4, operable relative to circles or scales IS for integrating watthours or kilowatt hours, as in the usual meter construction.

In Figure 2A of the drawings it will be observed that a gear train, shown generally at I8, is provided for rotating the pointers Il, I2, I3 and I4 in the proper relationship. The gear train IB is driven by a pinion I3 on a shaft 20 that is provided with a star wheel 2l with which a dog 22, carried by a shaft 23, has driving engagement. The shaft 23 is provided with a worm wheel 24 that is driven by a worm 25 on a meter spindle 26 which supports the usual disc 21 of a watthour meter. The disc 2l, as previously indicated, is caused to rotate at a speed depending upon the rate at which energy is ,being used in the circuit to which the windings of the electromagnets are connected. It will be understood that the meter spindle 26 may be driven by any other suitable means which operates as a function of a varying quantity, certain characteristics of which it is desired to measure.

As has been previously set forth, the indication that is provided by the pointers II, I2, I3 and I4 does not tell the whole story as to the demand that has occurred on the system. All that they show by their positions relative to the circles or scales I is the total amount of energy that has flowed in the circuit at the time that they are read. They cannot, of course, give any indication of the demand at any particular time.

For the purpose of providing an indication of the maximum demand during a demand period that has occurred in any demand interval therein, and also to pr-ovide an indication that will remain unchanged throughout the next demand period, demand pointers 3|, 32, 33 and 34 are provided. These pointers are arranged to rotate relative to demand circles or scales `to provide the indication of maximum demand.

It is desirable that the meter reader have some indication of the amount of the maximum demand that has occurred in the preceding demand period, For this purpose a test dial pointer 36 is provided and is arranged to rotate relative to a test scale 37 which may be calibrated in any suitable arbitrary umts. Near the end of the scale 3l there is provided a specially marked portion 38 which, when the test dial pointer 36 has been moved over it, shows to the meter reader that the maximum demand capacity of the register Ill has been exceeded during the previous demand period. As will be readily understood, suitable changes are then made in the register I0 or a new one is substituted, or other changes are made in order to provide for properly registering the maximum demand that is likely to occur.

It will be understood that the demand pointers 3 I, 32, 33 and 34 remain in the positions to which they have been advanced at the end of each demand period. The difference between the new reading and the previous reading gives the maximum demand that has occurred in a demand interval during the previous demand period. For the purpose of advancing the demand pointers 3l, 32, 33 and 34, for restoring the test dial pointer 36 to its initial position, and for performing several other functions which will be presently described, a manual reset arm 39 is provided having a lug 40 at one end for engagement by a suitable manual reset mechanism which is customarily located in the cover of the meter. Since the manual reset mechanism in the cover is old and well known, it is not shown or described herein. It will be understood that it is preferably of the type which can be operated in one direction only and that it is arranged to be sealed to prevent unauthorized operation.

After certain test operations have been completed and the demand pointers 3|, 32, 33 and 34 have been advanced during the test, it is desirable to restore them to their previous positions with respect to the demand circles or scales 35. For this purpose a reset member 4I is provided having a slotted head for engagement by a screwdriver. Rotation of ythe reset member 4I in the vdirection indicated by the arrow associated therewith will cause a reverse rotation of the demand pointers 3|, 32, 33 and 34, as will be described in detail hereinafter.

It will be recalled that the pinion I9, Figure 2A, which drives the gear itrain I8, is mounted on the shaft 20 that is driven by means Which operates as a function of certain characteristics `of a variable quantity that is being measured. The rotation that is imparted to the shaft 20 is employed for effecting the operation of the cumulative demand register in a manner that will now be set forth.

On the shaft 20 there is provided a pinion 44 which engages a gear wheel on a shaft 43 that is mounted at one end 41 in a fixed bearing and at the other end 48 in a plate 49 that is rockably mounted at t. is mounted on the plate 49 for urging a pinion 5t, on the shaft 45, into driving engagement witha gear wheel 55 on a shaft 55. It will be understood that when the plate is rocked about its axis at 5i) in a clockwise direction, the pinion 54 is moved out of driving engagement with the gear wheel 55. distinct means for rocking the plate 4t to effect disengagement of the pinion v54 from the gear wheel 55, which will be described hereinafter.

It will be observed that the shaft 56 extends from Figure 2A to Figure 2B and that, in the latter gure, a pinion 5'!Y is mounted thereon and that -it engages a gear Wheel 58. The gear wheel 53 is mounted on a hub59 and is urged into frictional engagement with a iiange thereof by a spider spring 5B. Ordinarily the gear wheel 53 and the hub 59.V rotate conjointly but, in certain instances, the hub 59 may rotate relative.

to the gear wheel 53 to prevent damage to the gear train I8 forming a part of the meter register if the apparatus is subjected to a demand that is beyond its range of operation.

The hub is mounted -for rotation with a hub Si which extends from a pinion B2 that is mounted for rotation on a shaft E5. The pinion 62 carries with it a pusher arm 5d, the inturned end t5 of which is arranged to engage a stud 56 carried by a demand wheel 61. The pusher arm 54 corresponds to the pusher arm that is employed in the maximum demand registers of the prior art for advancing the maximum demand painter along its scale. In like manner the demand wheel 51 corresponds to the maximum demand pointer and it is adapted to remain in the position to which it is operated by the pusher arm E4, the extent of movement ofthe demand wheel 61 during the demand period corresponding to the maximum demand in any demand interval during that period.

The demand Wheel 6l is mounted for rotation with a pinion 58 on a hub 69 that is coaxial with the shaft E3.

When the pinion 54, Figure 2A, is moved out of engagement with the gear wheel 55, the pusher arm t4 is reset to its initial position. This is accomplished by means of a gear sector '13, Figure 2B, which meshes with the pinion B2 and which is carried by an arm 'lf3 that is rockably mounted at '15. The arm 'M is provided with counterweights 75 which, when the driving engagement between the pinion 54 and the gear wheel 55 is released, urges the sector 'l5 downwardly and thereby rotates the pinion E52 and the pusher arm 54 in a counterclockwise direction.

The pusher arm 54 is stopped in its initial position when the inturned end 55 engages the upper face of the outer end 'll of a stop lever 13 that is rockably mounted at '59. A counterweight 85 is provided adjacent the tail end 3! of the stop lever i8 and is so arranged that the restoring force of the counterweights 'l5 on the pusher arm 54 is ineffective to rock the stop lever 1S. When the demand pointers 3l, 32, 53 and 35 are manually reset at the end of the demand period, suiiicient additional force is applied to the pusher arm 64 to rock the stop lever 'I8 in a clockwise direction until the tail end 8i engages an adjusting screw 82 that is threaded in` a support member 33 and locked in position by a lock nut 8d, rI'his further movement of the pusher arm 64 is provided to compensate for back lash A counterweight 5lY There aretwo separate andvonce during each demand interval.

in the gear train thaty is driven by the demand wheel 51, as will be apparent hereinafter.

It will` be noted that the pinion 68, which rotates with thev demand wheel 61, is arranged to drive through the gear wheels 81' and 88 the test dial pointer 35 which is mounted on a shaft 85 with the gear wheel 83. The movement of the test dial pointer 36 then corresponds to the movement of the demand wheel 61 during a demand period.

In Figure 2A of the drawings there is shown the mechanism for effecting the disengagement of the pinion 54 from the gear wheel 55 at the end of each demand interval, i. e., at the end of either iifiteen minutes or thirty minutes, to permit the counterweights 'i6 (Figure 2B)` to move the sector 'F3' downwardly for resetting the pusher arm 54' to its initial position in er1-- a worm 92 which is in engagement with -a worm wheel 83 that drives through a gear traink 94 a gear wheel 95. Preferably, the speed of the motor Si and the reduction lprevided by the gear train 94 is suchthat the gear wheel 95 rotates ln other words, the arrangement is preferably such that the gear wheel 95 rotates once every fifteen minutes or once every thirty minutes, as the case may be.

The gear wheel 95 is mounted for rotation on a hub 95 and is urged into frictional engagement with a flange 91 thereof by a coil compression spring 95. This frictional coupling is provided in yorder to permit manual rotation of cams 10i) and lEl-I, described hereinafter, so that the beginning ofthe demand. interval can be set for a particular time.

The hub 96 is mounted for rotation with a shaftQS that carries a pair of cams I and IUI thatare spaced by a washer m2.. A pair of levers. 151i and E05 is provided for cooperating with the cams itil and Ill-I, respectively. The lever tot is rockab-ly mounted at iil while the lever 05 is rockably mounted onthe lever i134 at lill. The distance between, the axis HB7 of the lever @55v and the endg 53 of the lever H34 adjacent the cam lili? is slightly greater than the distance between the axis l'l and the end M9 of the lever H35y adjacent the cam it, so that, on rotation of the cams mit and lili in a clockwise direction, the end It@ of the lever li5drops oif of its cam Mit slightly inI advance ofthe end H08 of the lever it@ droppingA off of its cam Hit. This arrangement then permits the lever H35 to rock relative' to the lever its, during which time the extension li! of the lever m5 engages andr lifts an armi H2 extending from the plate (i9. The platerdd moves with the arm H2. and thereby moves the pinion 5ft out of rengagement with the gear wheel 55. Sincethe shaft 45 is comparatively long and the movement thereof required to disengage the pinion 54 from the gear wheel 55. is relatively slight, it will be understood that this movement will takeplacev even though the end 4t' of the shaft 48 is mounted in a fixed bearing, sufficient clearance being provided in this bearing. to permitl this movement.

As soon as the end 58 of the lever E84 drops off of its cam iili, the extension lil of the lever i555 is moved' out of engagement with the arm i I2 and the counterweight 5| then immediately swings the plate 49 in a counterclockwise direction to move the pinion 54 back into driving engagement with the gear wheel 55. The time that they are out of engagement is that required to move the cam |93 after the lever |65 has been released to release the lever |64.

The downward movement of the lever |05 is eiected principally by a counterweight 3 assisted by a leaf spring ||4,

With a view to preventing the cams |39 and IM being advanced as a result of the movement of the levers |94 and |95, a spring finger H6 is provided for engaging the shoulder 3l of the hub 96.

The mechanism that is operated as a result of the forward movement of the demand wheel B1 will now Ibe described. This is shown in Figure 2B and includes three shafts |2|, |22 and |23 that are arranged to be rotated at successively slower speeds. These speed reductions are provided by a pinion |24 on the staff |2| engaging a gear wheel |25 on the staff |22 on which there is also mounted a pinion |26 meshing with a gear wheel |21 on the staff |23. The gear reduction is such that for each 100 revolutions of the staff |2I, the stair |22 rotates ten times and the staff |23 rotates once. Obviously, any other suitable gear reduction can be employed but the one mentioned is preferred for obvious reasons.

The staif |2| is driven through a spider spring |28 by a gear wheel |29. The spider spring |28 forms a friction clutch between the stai |2| and the gear wheel |29 so that rotation of the latter is permitted while the former is held stationary during the resetting operation, as will be presently described.

The gear wheel |29 is driven by a gear wheel |30 mounted on a shaft |3| carrying a gear wheel |32. The gear wheel |32 meshes with a gear wheel |33 on a shaft |34 which carries a gear wheel |35 that meshes with and is driven by the demand wheel 61.

It will now be apparent that the staffs |2|, |22 and |23 are rotated by the demand wheel 6'! during a demand period through an extent that corresponds to the extent of movement of the demand wheel 67 during this period. Obviously, only a single staff |2| might be employed or more than three staffs might be employed, as conditions may warrant. It will be understood that, since the demand wheel 61 is advanced by the quantity measuring mechanism, i. e., the disc 27, the staffs |2|, |22 and |23 are likewise advanced by the quantity measuring mechanism.

Now when the demand pointers 32, 33 and 34, which it will be recalled remain stationary during the demand period and during the advancement of the staffs |2|, |22 and |23, are advanced at the end of the demand period so that their positions correspond to the positions of the staffs |2l, |22 and |23, respectively, they will indicate the maximum demand that has occurred in the preceding demand period. The mechanism for advancing the demand pointers 32, 33 and 34 to the positions for indicating the maximum demand will now be described.

The staff |2| is provided with a ratchet wheel |39 having a single tooth |40. The tooth I4!! is arranged so that it is free, when the wheel |39 is rotated in a counterclockwise direction, the only direction in which it is permitted to rotate, so that it slips past a spring pawl |4| that is mounted for rotation with a hub |42 on which the demand pointer 32 is also mounted. It will be understood that the spring pawl 4|, hub |42, and demand pointer 32 rotate together as a single unit. It will also be understood that, during the demand period, they remain stationary while the ratchet wheel |39 rotates through one or more revoluti-ons relative thereto.

The staff |22 is provided with a nger |43 that is positioned so that it 'can be engaged by a stop |44 that is carried by a hub 55 which also carries the demand pointer 33. The stop |44, together with the hub |45 and the demand pointer 33 are arranged to rotate together as a unit.

On the staff |23 there is provided an arm similar to the arm |43 on the stan' |22 and the demand pointer 34 is provided, like the demand pointer 33, with a stop which corresponds to the stop |44. Since the construction is a duplicate of that for the demand 33, it is not shown.

Since it is intended that the staff |2| will be rotated through more than one revolution during a demand period, it is necessary to provide the pawl and ratchet arrangement as is provided by the ratchet wheel |39 and the spring pawl 4L However, since the stai |22 will not be rotated through more than a single revolution during a demand period, it is unnecessary to provide it with a pawl and ratchet arrangement. The simple finger and stop arrangement provided by the nger |43 and stop |44 is all that is necessary for the staff |22. Of course, since the staff |23 rotates at a much slower speed than does the stai |22, this arrangement will also suffice for it.

With a view to advancing the demand pointer 32 to a position corresponding to the position to which the stai? |2| has been rotated during a demand period, a gear wheel |43 is provided and is rotatably mounted on the hub |42. A spring spider |42 serves to provide a friction drive between lthe gear wheel |45 and the hub |42. On rotation of the gear wheel |45 the demand pointer 32 is rotated in the same direction that lthe staff |2| is rotated until the spring pawl |4I engages and is stopped by the tooth |43 of the ratchet wheel |39. Further movement ci the demand pointer 32 is thereby prevented but the gear wheel |33 is permitted to rotated further because of the friction drive provided by the spring spider |47.

For advancing the demand pointer 33 to a position corresponding to the position of the stai |22, a gear wheel |48 is provided and is rotatably mounted on the hub |45. A spring spider |49 provides a friction drive between the gear wheel |48 and the demand pointer 33 so that on rotation of the former the stop |34 is carried into engagement with the nger |43. When this engagement occurs, no further movement of the demand pointer 33 is permitted. However, because of the frictional engagement provided by the spring spider |49, the gear Wheel |48 can continue to rotate.

A gear wheel |53 is provided for advancing the demand pointer 34 to a position corresponding to that of the staff |23. Since the relationship between the gear wheel |52 and its demand pointer 34 is the same as the relation between the gear wheel |43 and its demand pointer 33, a description thereof is not set forth herein.

The demand pointer 3| is advanced with the demand pointer 32 but at a higher speed. It will be observed that a gear wheel |5| is provided on the hub |42 for rotation therewith and that it meshes with a pinion |52 that is fastened on a shaft |53 Which carries the demand pointer 3|., The ratio between the gear Wheel and the pinion |52 is preferably such that for each revolution of the former the latter makes ten revolutions.

Since it is necessary to rotate the demand rpointers 32, 33 and 34 through less than a complete revoluticn in order to advance them into positions corresponding to their respective staffs |2|, |22 and |23', the gear `Wheels |46, |148 and |56, which effect this advancement, and which are placed in driving engagement, can have the same numbers of teeth.

The gear Wheels |46, |55 and |55 are driven in the order named through an idler gear wheel `|511 by a gear Wheel |55 that is rotated by the manual reset arm 39 in a manner that will be hereinafter set forth.

A dog |5 biased into engagement 'with 'the teeth of the gear AWheel |55 is arranged'to vpermit rotation thereof in a forward or a counterclock- Wise direction but prevents rotation thereof Ain a reverse direction.

While the demand pointers 3|, vand 34 are being advanced at the end of a demand period to positions corresponding to the positions to which the staffs lZl, |22 and |23 have been advanced by the demand wheel 51, it is desirable that the staffs |21, |22 and |23 be blocked so that the demand pointers 31, 32, 33 and 34 can be precisely advanced to positions corresponding exactly with the maximum demand during the preceding demand period. VFor this purpose a blocking mechanism for 4the staffs 12|, VI|22 and |23 is provided that is automatically operated at the beginning of the resetting cycle .to prevent movement of these staffs during the cycle.A One manner of effecting this rblocking action is to provide a gear Wheel |51) .on the .staff |21 meshing with apinion |66 on a shaft |5| that also carries a gear wheel |52. At the beginning of the resetting cycle a blocking spring |63 is moved so `that its tip I6@ engages between a pair of teeth of the gear ywheel |62 so that rotation thereof is prevented as long as the tip |64 is' thus engaged. Since the gear wheel |62 is fastened onto the shaft and since this shaft and the staffs |.2|, |22 and |23 are positively -intergeared, no movement of the staffs |2|, |22 and |23 is permitted as long as the blocking spring loccupes the blocking position. Of course, the blocking spring |53 is moved out of engagement with the gear wheel |52 to permit further advance of the staffs |2|, |22 and |23 during the next demandperiod. The mechanism for operating the blocking spring |63 will be presently described.

It will be recalled that the manual reset arm 39 is provided for resetting the cumulative demand register at the end of a demand period. As shown in Figure 2B, the manual reset arm 39 is mounted for rotation With a -shaft |66 ythat. carries close to its rear end a heart-shaped V`cam |51in the V-shaped portion |51 of which a pin |63 is normally positioned. `The pin |266 isucarried by a lever |59 that is biased by A.a lcoil tension spring .|16 so V.that the pin |68 always remains in contact engagement with the periphery of .the heart-shaped cam |61. It will be understood that the initial movement of the manual reset arm `56 in a counterclockwise `direction immediately lifts the pin |58 out ofthe V-shaped section |51 a corresponding movement of the lever |65 is effected. On the ccmpletion of a rotation 0f the heart-shaped cam |61, the V-shaped portion |61' is veffective to automatically center .the shaft |66 and the manual reset arm 39 in the initial position, as. will be readily understood, thereby making it unnecessary for an accurate alignment of the manually -operable means extending through themeter cover for engagement `with the manual reset arm 39.

A The lever |59 is rockably mounted at |69 and it carries a finger |1| that engages a pin |12 on the ydownwardly extending leg |13 of a blocking lever, shown generally at |14.

It will be observed that the blocking lever |14 is mounted for rotation With a shaft |15. A hub '|16 is provided on an extension of the shaft |15 to which, it will be noted, the blocking spring |63 is secured. It will now be understood that the blocking spring |53 is moved so that its tip |64 engages the gear wheel |62 as ysoon as the blocking lever |14 has been rotated during the beginning of the resetting cycle by the movement of the pin |68 out of the V-shaped portion |61 Yof the heart-shaped cam |61.

The blocking lever |14 is `providedwith a geny, erally horizontal leg |11 which extends from Figure 2B to Figure 2A. At its extreme end |18 the leg |11 of the blocking lever |14 vis arranged to engage the pin H2 carried by the plate 49. The plate 49 is moved -to disengag-e the pinion 54 from the gear Wheel 55 so that the driving connection to the cumulative 'demand register Will be interrupted.

It will be recalled that the levers |64 and |65 effect a similar movement Aof the plate 49. However, they are arranged to interrupt the driving engagement of the pinion 54 with the gear wheel 55 only momentarily, so that there-Will be a minimum time between demand intervals. However, at -the end of a demand period, the plate 49 is held in the disengaging position by the end |18 of the leg |11 of the blocking lever |14 for a time which isa substantial portion of a `demand interval, as will be presently apparent.

A counterweight |16 is provided, as illustrated, on the leg |11 of the yblocking lever |14 in order to urge the same to the normal or releasing position.

It is desirable to held the plate 49 in the position Where the pinion-54 is disengaged from the gear Wheel 55 for `an appreciable time interval after the demand pointers 3|, 32,33 and `34 have been advanced by rotation of the manual reset arm 39. If this time delay Were not provided, then it would be Ypossi-ble for the meter reader to effect a second resetting operation shortly after he had completed the rst one, with the result that the demand in the brief interval would-be added to the previously registered cumulative demand. This is undesirable for obvious reasons.

With a view to providing this desired time interval the leg |11 of the blocking lever |14 is provided --With a depending-finger having a cam surface 68| that engages the surface of the interval cam shaft 99 -at lill-'when the blocking lever l 14 isV rotated in a clockwise direction tothe resetting position by the heart-shaped cai-*11161 as previously described. The Aengage-ment between the cam surface |161 Vand the surface |82 of the shaft is Ysuchthat Vtheblocking lever |14 is heldinthe resetting position after the heartshaped cam |61 has been returned to its normal position.k This .operation yis permitted since the finger |1| is not fastened to the pin |12.

Y Now it will be recalled that the interval cam shaftg is rotated at a speedV of one revolution during each demand interval. The cam surface |8| is so arranged that the blocking lever |14 will be released from the resetting position in about one-third of a revolution of the interval cam shaft 99. This then provides an interval of from five to ten minutes during which the manual reset arm 39 can be operated through as many cycles of operation as the meter reader may desire, but none of them after the irst will be effective to advance the demand pointers 3|, 32, 33 and 34. At the end of this time delay period, the blocking lever |14 is released and it drops to the normal position. The blocking spring |63 then is moved out of engagement with the gear wheel |62 and, since the plate 49 has been released, the pinion 54 is again placed in driving engagement with the gear wheel 55.

In Figure 4 of the drawings the blocking lever |14 is shown in side elevation and its relationship to the plate 49 and to the surface |82 of the shaft 99 is more clearly illustrated.

It will be recalled that the gear wheel |55 which drives the gear wheels |46, |48 and |50 through the idler gear wheel |54 advances the demand pointers 32, 33 and 34 to positions corresponding to the positions to which the staffs |2l, |22 and |23 have been operated by the demand wheel 61. It is desirable that the movement of the gear wheel |55 be delayed until after the blocking spring |63 has arrested further movement of the staffs |2|, |22 and |23 and the driving engagement between the pinion 54 and the gear wheel 55 has been interrupted, so that the demand pointers 3|, 32, 33 and 34 can be advanced precisely and accurately to the new positions representing the maximum demand that has occurred in the preceding demand period. In order to effect this desired sequence of operations the gear wheel |55 is mounted for rotation with a hub |65 that is provided with teeth |86 around its periphery. In the embodiment shown four teeth |86 are provided and they are arranged to be engaged by a pawl |61 that is resiliently urged into engagement by any suitable means, such as a spring |88. It will be understood that the coil tension spring |88 is shown for illustrative purposes only, and that any other suitable form of resilient means can be employed for urging the pawl |81 into engagement with the hub |65. The pawl |81 is rockably mounted on an arbor |69 that extends from avdisc |90 fastened onto the shaft |66. A collar |9| mounted on a stationary shaft |92 is arranged in the path of the tail |63 of the pawl |61 so that near the completion of a revolution of the manual reset arm 36, the forward end of the pawl |81 is caused to disengage the particular tooth |36 with which it may be in engagement, thereby continuing to the normal position out of driving engagement with the hub |85.

It will now be understood that the initial movement of the manual reset arm 39 is ineffective to cause rotation of the gear wheel |55 for advancing the demand pointers 3| 32, 33 and 34 until the forward end of the pawl |81 engages the next tooth |86 on the hub |85. During this interval, the heart-shaped cam |61 has rotated so that the pin |68 will have been moved out of the V-shaped portion |61 and during this interval the blocking spring |63 engages the gear wheel |62 and the driving engagement between the pinion 54 and the gear wheel 55 is interrupted.

It will be understood that the demand Wheel 61 is reset to the initial position at the end of a demand period when the demand pointers 3|, 32, 33 and 34 are advanced. However, the resetting of the demand wheel 61 is effected independently of the advancement of the demand pointers 3|, 32, 33 and 34. It so happens that both operations are effected by the single rotation of the manual reset arm 39 but, nevertheless, the resetting of the one and the advancement of the other are not interrelated except in so far as it happens that both are effected by the same driving means. In other words, they are not synchronized.

With a vieW to resetting the demand wheel 61 to its initial position a gear sector |91 is provided in engagement with the pinion 68 which, it will be recalled, rotates with the demand wheel 61. The gear sector |91 is moved in a downward direction when the demand wheel 61 is advanced. It is moved in a reverse direction to reset the demand Wheel 61, as will be readily understood.

The gear sector |91 is carried at one end of a sector arm |98 that is rockably mounted on a shaft |99. The pin 200 extends from the sector arm |98 and carries an adjusting screw 20| that may be locked in position by a lock nut 202. The adjusting screw 20| is arranged to engage one leg 203 of a lever, shown generally at 204, which includes a leg 265 that is limited in its movement by a stop 206.

The leg 205 of the lever 264 is arranged to be engaged by thev outturned end 201 of an arm 208 which is carried by the shaft |66. This engagement takes place some time after the blocking spring |63 has been moved to block further rotation of the shafts |2|, |22 and |23 and after the driving engagement between the pinion 54 and the gear wheel 55 has been disrupted. The engagement can take place after the pawl |81 engages one of the teeth |86 and initiates the forward movement of the demand pointers 3|, 32, 33 and 34, since there is no relation between the advancement of these pointers and the resetting of the demand Wheel 61 to its initial position.

When the driving engagement between the pinion 54 and the gear wheel 55 is disrupted by movement of the plate 49 on operation of the blocking lever |14 during the resetting operation, the pusher arm 64 is restored to its initial position automatically by the counterweights 16. The initial position of the pusher arm 64 is determined by the position of the end 11 of the stop lever 18. When the outturned end 65 of the pusher arm 64 engages the end 11 of the stop lever 18, then the pusher arm 64 is considered to be in its initial position. The counterweight on the stop lever 18 is of such a character that no permanent displacement of the stop lever takes place when it is engaged solely by the pusher arm 64.

Now when the demand wheel 61 is reset by movement of the gear sector |91, it carries with it the stud 66 against which the outturned end 65 of the pusher arm 64 reacts in advancing the demand wheel during a demand interval. In its initial position the stud 66 bears against the pusher arm 64 and urges it against the end 11 of the stop lever 18 with a force in addition to that which is provided by the counterweights 16. The relationship of the various parts concerned with the resetting of the demand wheel 61 is more clearly illustrated in Figure 3 of the drawings.

W'hen the demand Wheel 61 is reset to its initial position while the blocking spring |63 prevents rotation of the gear wheel |62 and the associated parts, as previously described, it will be understood that there is a certain amount of backlash between the demand wheel and the gear wheel H52 that is blocked by the blocking spring |63. It will be understood that a certain amount of back lash is inherently present in a geared construction as disclosed. The initial movement of the demand Wheel 67 in the resetting direction rst takes up the back lash through the gear wheels and pinions that may be enumerated in consecutive order from the demand wheel El through |35, |33, |32, |30, |29, |59, |68, to the gear Wheel |62 that is blocked by the blocking spring H53. When this back lash is taken up, then the spider |28 permits movement of the gear wheel |29 relative to the blocked stanc i2! for continued movement of the demand wheel El' in the resetting direction.

Compensation for this back lash is provided by permitting the pusher arm G4 to be moved slightly past what is otherwise its normal initial position at the beginning of each demand interval by an amount that is determined by the gap between the tail end 8| of the stop lever '|8 and the lower end of the adjusting screw 82. Then for the first demand interval in the next demand period the pusher arm Will start from a position slightly in advance of its normal position to take up this back lash.

The movement of the stop lever 18 in a counterclockwise direction when it is not engaged by the pusher arm @t can be limited by any suitable means, such as by a stop '2(19.

The sequence of operation of the cumulative demand register will now be brieiiy reviewed in order to provide a complete description in one portion hereof where the various functions will be more clearly correlated.

The pointers li, |2, i3 and is will be operated continuously without regard to any functioning of the cumulative demand register. The operation of this register will be substantially as follows.

At the beginning of a demand period after the demand pointers 3 ,32, 33 and 34 have been reset, the pusher arm e4 is advanced in accordance with the demand during the next demand interval and it carries with it the stud 66 and thereby the demand wheel E?. The pusher arm ed is periodically reset under the control of the timing mechanism including the synchronous motor 9|. The demand wheel 6l remains in the position to which it has been operated by the maximum movement of the pusher arm 54. Any movement of the pusher arm 66| less than this maximum movement has no eiect on the operation of the demand wheel 6l'.

The demand Wheel 6l advances the staffs |25, |22 and |23 through the interconnecting gear train, so that they take up positions corresponding to the position to which the demand wheel 6l has been advanced through the maximum extent of movement of the pusher arm 6d, which corresponds to the maximum demand during any demand interval in the demand period. The

test dial pointer 3S is also advanced with the advance of the demand wheel 6l. During the demandperiod, however, the demand pointers 3|, Si?, 33 and fi rem-ain stationary in the positions to which theyhave been operated at the end of the preceding demand period. It will be understood that this permits a checking of the maximum demand reading for the preceding demand period during the next demand period.

When the register is to be read, `the meter man rotates the manual reset arm -39 through one complete revolution. As a result -of this, further movement of the stais |2|, |22 and |23 is blocked by the blocking spring |3 and the driving connection to the demand wheel 67 is interrupted by moving `the pinion 54 out of engagement with the gear wheel 55. The pawl |81 then engages one of the teeth |86 and the gear wheel |55 is rotated to rotatethrough the idler gear Wheel |54 the gear wheels'l, M8 and |53 to advance the demand pointers 32, 33 and 3d to positions corresponding to the positions to which the staffs |2|, |22 and |23 have been rotated, and in which positions they are blocked by the blocking spring |63. During this forward movement of the demandpointers?, 33and 34, the demand pointer '3i is advanced at a speed 'that is ten times that of the speed of movement of the demand pointer .32.

The demand Wheel 6T is reset to an initial position in which compensation is provided for back lash between `it and the gear wheel |62, as previously described. The driving connection to the pusher arm '54 and the demand Wheel 61 is maintained interrupted and the staffs |25, |22 and |23 remain in the blocked condition until after the blocking lever |14 is released by movement ofthe cam surface |8| of the finger lili] out of frictional engagement with the surface |82 of the intervalv cam shaft 9S. When the blocking lever il@ is released, the cumulative register is again placed in -driving connection with the quantity measuring mechanism.

It was previously indicated that the reset member 54| is provided for moving the-demand pointers 3|, 32, 33 and Sli in a reverse direction after certain tests have been made on the register. As shown in Figure 2B, the reset member 4| is carried by a spring strip 2 ii and has mounted thereon a pinion 2|| that can be placed in driving engagement with the gear wheel |59 on the lstaii |2|. On rotation of the reset member di in .the direction indicated bythe arrow associated therewith in Figure 1, itis possible to restore the demand pointers 3|, 32, 33 and 34 to the positions that they occupied at the beginning of the test. On release of the reset member-i, the spring strip 2|@ moves the pinion 2|| out of driving engagement with the gear wheel |59.

Not only does the stop lever 18 compensate for back lash, as described but it also can be used to counteract the tendency, from whatever cause such as the random meshing of the pinion 5t with the gear wheel 55, for the register indication to be low.

Since Vcertain further changes may be made in the above construction and diierent embodiments of the invention may be made without departing from the scope thereof, it is intended. 'that all matter contained in the above descripfor periodically'resetting said iirst member to its initial position, a second resettab'le member mov-- `able from an initial position through `an extent depending upon themaximum extent of movement of said first member during a plurality of resetting periods, means for resetting said second mem-ber to its 'initial position, a mem-ber unidirectionally movable through an extent depending upon the maximum extent of movement of said second member, an indicator and a scale relative to which the indicator moves, and means operable independently of sai-d unidirectionally movable member for moving said indicator into a position corresponding to that of said unidirectionally movable member in which position the measurement is indicated.

2. Means for indicating a measurement comprising, in combination, a first resettable member movable from an initial position through an extent depending upon a varying quantity, means for periodically resetting said iirst member to its initial position, a second resettable member movable from an initial position through an extent depending upon the maximum extent of movement of said rst member during a plurality of resetting periods, a third member advanced with the forward movement of and through an extent depending upon the maximum extent of movement of said second member, an indicator and a scale relative to which the indicator moves, and manually operable means arranged and adapted to reset said second member to its initial position and to advance said indicator in the same direction as said third member is advanced to a position corresponding thereto whereupon the measurement is indicated.

3. Means for indicating a measurement comprising, in combination a resettable member movable from an initial position through an extent depending upon a varying quantity, means for periodically resetting said member to its initial position, a member movable through an extent depending upon the maximum extent of movement of said resettable member during a plurality of resetting periods, an indicator and a scale adjacent to which the indicator moves, said indicator being movable into a position corresponding to that of the last named movable member in which position the measurement is indicated, and means for preventing further movement of said indicator after the same has been moved to its indicating position until a predetermined interval has elapsed.

4. Means for indicating a measurement comprising, in combination, a first resettable member movable from an initial position through an extent depending upon a varying quantity, means for periodically resetting said rst member to its initial position, a second resettable member movable from an initial position through an extent depending upon the maximum extent of movement of said rst member during a plurality of resetting periods, means for resetting said second member to its initial position, a member unidirectionally movable through an extent depending upon the maximum extent of movement of said second member, an indicator and a scale relative to Which the indicator moves, means for moving said indicator into a position corresponding to that of said unidirectionally movable member in which position the measurement is indicated, and means for preventing movement of said unidirectionally movable member While said indicator is being moved to its indicating position.

5. Means for indicating a measurement comprising, in combination, a first resettable member movable from an initial position through an extent depending upon a varying quantity, means for periodically resetting said rst member to its initial position, a second resettable member movable from an initial position through an extent depending upon the maximum extent of movement of said first member during a plurality of resetting periods, a third member advanced with the forward movement of and through an extent depending upon the maximum extent of movement of said second member, an indicator and a scale relative to which the indicator moves, manually operable means arranged and adapted to reset said second member to its initial position and to advance said indicator in the same direction as said third member is advanced to a position corresponding thereto whereupon the measurement is indicated, and means operated by said manually operable means for preventing movement of said third member while said indicator is being advanced to its indicating position.

6. Means for indicating a measurement comprising, in combination, a pusher arm rotatable from an initial position through an extent depending upon a varying quantity, biased stop means engageable by said pusher arm for determining its initial position, means for periodically resetting said pusher arm to its initial position in engagement with said biased stop means, a demand Wheel driven from an initial position by said pusher arm and disposed to remain in the position to Which it is driven thereby, a staff, a gear train operatively interconnecting said demand Wheel and said staff for rotating the latter through an extent depending upon the maximum extent of movement of the former, means for resetting said demand Wheel to its initial position by rotating the same in a reverse direction carrying therewith said pusher arm against said biased stop means and moving the same past the position thereof corresponding to the initial position of said pusher arm, an indicator and a scale relative to which the indicator rotates, and means for rotating said indicator into a position corresponding to that of said staff in which position the measurement is indicated.

7. Means for indicating a measurement comprising, in combination, a pusher arm rotatable from an initial position through an extent depending upon a varying quantity, biased stop means engageable by said pusher arm for determining its Vinitial position, means for periodically resetting said pusher arm to its initial position in engagement with said biased stop means, a demand wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a staff, a gear train operatively interconnecting said demand wheel and said staff for rotating the latter through an extent depending upon the maximum extent of movement of the former, means for resetting said demand Wheel to its initial position by rotating the same in a reverse direction carrying therewith said pusher arm against said biased stop means and moving the same past the position thereof corresponding to the initial position of said pusher arm through an extent depending substantially upon the amount of back lash in said gear train whereby compensation for the same is provided, an indicator and a scale relative to which the indicator rotates, means for rotating said indicator into a position corresponding to that of said staff in Which position the measurement is indicated, and means for preventing rotation of said staiic While said indicator is being rotated to its indicating position.

8. Means for indicating a measurement comprising, in combination, a pusher arm rotatable from an initial position through an extent depending upon a varying quantity, biased stop means engageab-le by said pusher arm for determining its initial position, means for periodically resettingsaid pusher arm to its initial position in engagement with said biased stop means, a devmand Wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a stai, a gear train operatively interconnectingrv said demand wheel and said stair for rotating the latter through an extent depending upon the maximum extent of movement of the former, means for resetting said demand wheel to its initial position by rotating the same in a reverse direction carrying therewith said pusher arm against said biased stop means and moving the same past the position thereof corresponding to the initial position of said pusher arm through an extent depending substantially upon the amount of back lash in said gear train whereby compensation for the same is provided, an indicator and a scale relative to which the indicator rotates, means for rotating said indicator into a position corresponding to that of said stair in which position the measurement is indicated, and means for' preventing further rotation of said indicator after the same has been rotated to its indicating position until a predetermined interval has elapsed.V Y

9. Means for indicating a measurement comprising, in combination, a pusher arm rotatable from an initial position through an extent depending upon a varying quantity, biased stop means engageable by said pusher arm for determining its initial position, means tor periodically resetting said pusher arm to its initial position in engagement with said biased stop means, a demand wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a stan, a gear train operatively interconnecting said demand wheel and said stair for rotating the latter through an extent depending upon the vmaximum extent of movement of the former, an indicator and a scale relative to which the indicator rotates, and manually operable means arranged and adapted to reset said demand wheel to its initial position by rotating the same in a reverse direction carrying therewith said pusher arm against said biased stop Vmeans and moving the same past the position thereof corresponding to the initial position oi" said pusher arm through an extent depending substantially upon the amount of back lash in said gear train and to rotate said indicator in the same direction as said staff is rotated to a position corresponding thereto whereupon the measurement is indicated.

l0. Means for indicating a measurement comprising, in combination, a pusher arm, means having driving connection with said pusher arm for rotating the same from an initial position through an extent depending upon a varying quantity, means for periodically interrupting said driving connection whereupon said pusher arm is returned to its initial position, a demand wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a stair rotated by said dem and wheel through extent depending upon the maximum extent of movement of said demand wheel, an indicator and a scale relative to which the indicator rotates, and manually opera- 1ole means arranged and adapted to reset said demand Wheel to its initial position and independently thereoic to rotate said indicator to a position corresponding to that of said stair.

l1. Means for indicating a measurement comprising, in combination, a pusher arm, means having driving connection` with said pusher arm for rotating the same from an initial position through an extent depending upon a varying quantity, means for periodically interrupting said driving connection whereupon said pusher arm is returned to its initial position, a demand wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a stai rotated by said demand Wheel through an extent depending upon the maximum extent of movement or" said demand Wheel, an indicator and a scale relative to which the indicator rotates, manually operable means arranged and adapted to reset said demand Wheel to its initial position and independently thereof to rotate said indicator to a position corresponding to that ofsaid staff, and a blocking member moved into operative engagement with said staff by said manually operable means for preventing rotation thereof while said indicator is being rotated to its indicating position.

12. Means for indicating a measurement comprising, in combination, a pusher arm, means having driving connection with said pusher arm for rotating the same from an initial position through an extent depending upon a varying quantity, means for periodically interrupting said driving connection whereupon said pusher arm is returned to its initial position, ademand Wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a staff rotated by said demand wheel through an extent depending upon the maximum extent of movement of said demand wheel, indicating means including nrst and second indicators geared together in such manner that the second indicator makes ten revolutions for each revolution of the first indicator and scales relative to which these indicators rotate, and manually operable means arranged and adapted to reset said demand Wheel to its initial position and independently thereof to rotate said indicators to positions corresponding to the position of said stai?.

13. Means for indicating a measurement comprising, in combination, a resettable member movable from an initial position through an eX- tent depending upon a varying quantity, means for periodically resetting said member to its initial position, a plurality of rotatable members taking up their positions according to the maximum extent of movement of said resettable member during a plurality of resetting periods; indicating means corresponding to each of said rotatable members and movable independently thereof, each indicating means including a rotatable indicator and a scale adjacent to which the indicator rotates, and means for moving each indicator into a position corresponding to that of the rotatable member individual thereto in which positions the measurement is indicated.

14. Means for indicating a measurement comprising, in combination, a i'lrst resettable member movable from an initial position through an extent depending upon a varying quantity, means for periodically resetting said first member to its initial position, a second resettable member movable from an initial position through an extent depending upon the maximum extent of movement of said first member during a plurality of resetting periods, means for resetting said second member to its initial position, a plurality of rotatable members taking up their positions according to the maximum extent of movement of said second member, indicating means corresponding to each of said rotatable members, each indicating means including a rotatable pointer and a scale adjacent to which the pointer rotates; and means for moving said pointers into positions corresponding to the positions of the rotatable members individual thereto in which positions the pointers indicate the advance of said second member prior to resetting thereof.

15. Means for indicating a measurement comprising, in combination, a rst resettable member movable from an initial position through an extent depending upon a varying quantity, means for periodically resetting said rst member to its initial position, a second resettable member movable from an initial position through an extent depending upon the maximum extent of movement of said rst member during a plurality of resetting periods, a plurality of rotatable members each after the iirst being driven by the preceding member at a successively slower speed With the rst rotatable member being advanced with the forward movement of and through an extent depending upon the maximum extent of movement of said second member; indicating means corresponding to each of said rotatable members, each indicating means including a rotatable pointer and a scale adjacent to which the pointer rotates; and manually operable means arranged and adapted to reset said second member to its initial position and to advance said pointers in the same direction as said rotatable members are advanced to positions corresponding to their positions whereupon the pointers indicate the advance of said second member and thereby the measurement.

16. Means for indicating a measurement comprising, in combination, a pusher arm, means having driving connection with said pusher arm for rotating the same from an initial position through an extent depending upon a varying quantity, means for periodically interrupting said driving connection whereupon said pusher arm is returned to its initial position, a demand wheel driven from an initial position by said pusher arm and disposed to remain in the position to which it is driven thereby, a plurality of stais each after the rst being driven by the preceding staff at one tenth of the speed of the preceding staff with the first stai being rotated with the forward movement of and through an extent depending upon the maximum extent of movement of said demand wheel; indicating means corresponding to each of said stais, each indicating means including a rotatable pointer and a scale adjacent to which the pointer rotates, said pointers being intergeared to rotate at the same speed with nonpositive driving means between the gearing and the pointers; and manually operable means arranged and adapted to reset said demand wheel to its initial position and independently thereof to rotate said pointers to positions corresponding to the positions of the stais individual thereto.

17. Means for indicating a measurement comprising, in combination, a pusher arm, means having driving connection with said pusher arm for rotating the same from an initial position through an extent depending upon a varying quantity, means for periodically interrupting said driving connection whereupon said pusher arm is returned to its initial position, a demand wheel driven from an initial position by said pusher' arm and disposed to remain in the position to which it is driven thereby, a plurality of staffs each after the rst being driven by the preceding staff at one tenth of the speed of the preceding staif with the first staff being rotated with the forward movement of and through an extent depending upon the maximum extent of movement of said demand wheel; indicating means corresponding to each of said staffs. each indicating 'means including a rotatable pointer and a scale adjacent to which the pointer rotates, said pointers being intergeared to rotate at the same speed with non-positive driving means between the gearing and the pointers; manually operable means arranged and adapted to reset said demand wheel to its initial position and independently thereof to rotate said pointers to positions corresponding to the positions of the staffs individual thereto, and a blocking member moved into operative engagement with said stais by said manually operable means for preventing rotation thereof while said pointers are being rotated into registration therewith.

ROSCOE H. WILMETH. 

